How to render video in H.265 HEVC?
For future reference.
Blender does support the H.265 HEVC equivalent made by google, WEBM/VP9
From VP9 Wikipedia:

VP9 is an open and royalty-free video coding format developed by
Google.
VP9 is the successor to VP8 and competes mainly with MPEG's High
Efficiency Video Coding (HEVC/H.265). At first, VP9 was mainly used on
Google's video platform YouTube.The emergence of the Alliance
for Open Media, and its support for the ongoing development of the
successor AV1, of which Google is a part, led to growing interest in
the format.

Example for VP9 output
File Format: FFmpeg video
Encoding container: MPEG-4
Video Codec: WEBM/VP9
Edited For clarification: While WEBM/VP9 is not exactly H265 HEVC, it is the performance equivalent and already on Blender.